Uploadable/downloadable manual crossfade learn feature

ABSTRACT

Disclosed is an audio follow video mixer incorporating a manual crossfade learn feature. According to the invention, an operator may set the mixer so that a custom crossfade operation performed manually is stored in memory. The custom crossfade can then be uploaded to a video editor unit where it may be stored in the edit decision list. Thereafter, the stored custom crossfade may be downloaded from the video editor.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to the following commonly owned-co-pending applications: "MANUAL CROSSFADE LEARN FEATURE FOR AN AUDIO FOLLOW VIDEO MIXER" (Attorney Docket No. SOA-036), Ser. No. 8/142,974 filed on Oct. 29, 1993, the disclosure of which is hereby incorporated by reference; and "UP AND DOWN-LOADABLE VTR CONFIGURATION FOR AN AUDIO FOLLOW VIDEO MIXER" (Attorney Docket No. SOA-035), Ser. No. 08/135,351, filed on Sep. 30, 1993.

FIELD OF THE INVENTION

This invention relates to editing of audio data using an audio follow video mixer system. More particularly, this invention relates to a crossfade learn feature for an audio follow video mixer.

BACKGROUND OF THE INVENTION

It is known that an audio mixer system may be advantageously used to edit several audio channels provided by several multi-channel devices such as video tape recorders (VTRs). In a typical configuration, several audio channels are input to an audio follow video mixer. The mixer can then be used to process the input audio channels according to various operations such as PREVIEW/REVIEW or FADE UP/FADE DOWN. Audio channels which are actively being processed may be monitored and output to other VTRs associated with the mixer.

In order to facilitate these various mixer operations, it has been found useful to provide several different operating modes for the mixer. For example, the mixer may be set to operate in an EDITOR mode in which an operator controls editor operations by use of video editor which provides various control signals to a mixer unit. In this mode, most of the mixer's local controls, which may be located on the mixer's console, will be disabled. Mixer operation is then controlled by commands supplied from the video editor. These commands are executed, for example, by means of software stored in the video editor as an Edit Decision List (EDL).

The mixer may also be set to operate in AUTO mode wherein various functions are initiated by the operator locally using the mixer console but are performed automatically by the mixer according to preset operating routines. Further, a mixer may be set for MANUAL mode operation. In this mode, the operator manually controls the various operations of the mixer using local controls located on the mixer console. For example, the operator may perform crossfades manually between selected audio channels. Manual control of the crossfade operation affords the operator the advantage of tailoring the manner in which the crossfade is performed, rather than being constrained to a particular preprogrammed crossfade.

However, prior art mixer systems in which crossfades are performed manually suffer the drawback that it is difficult for the operator to identically reproduce a particular crossfade operation. While an experienced operator may minimize this drawback by repeated practice, this requires additional time and expense in production.

There is therefore a need to provide a mixer which offers the flexibility afforded by manual operation along with ease in reproducing custom crossfades. There is a further need to provide enhanced versatility in reproducing custom crossfades by utilizing a video editor in reproducing custom crossfades.

SUMMARY OF THE INVENTION

A general object of this invention is to meet these, and other needs, as well as to overcome the aforementioned and other drawbacks of the prior art. This is accomplished by providing an audio follow video mixer system for performing a crossfade operation between a first audio channel having a first amplitude and a second audio channel having a second amplitude. This audio follow video mixer comprises an audio mixer device and a video editor. The audio follow mixer device includes: gain control means for adjusting the amplitude of the first audio channel and the second audio channel, in which the gain control means includes means for manually controlling the adjustment of the amplitude of the first audio channel and the second audio channel and means for providing signals indicating the adjustment made to the first audio channel and the second audio channel; mixer memory means for storing data corresponding to the signals; and mode select means for enabling the mixer to adjust the amplitudes of the first audio channel and the second audio channel according to said data stored in the memory means. The video editor of the system is operatively coupled to said audio mixer device and receives the data stored in the mixer memory means. The video editor includes editor memory means for storing said data and means for transmitting said data to said mixer apparatus.

According to an aspect of the invention, the audio mixer device of the audio follow video mixer system includes a central processing unit (CPU) operatively coupled to the mixer memory means.

According to another aspect of the invention, the audio follow video mixer system further includes a control member located on a display portion of the audio mixer device for enabling the control signals from the gain control means to be stored by the memory means.

According to yet another aspect of the invention, the audio follow video mixer system further includes a LED indicator for visually indicating that the control member has enabled the storing of said data.

According to still another aspect of the invention, the audio follow video mixer system further includes a transition start member for providing a crossfade initiate signal to the CPU, whereby the CPU, upon receiving the crossfade initiate signal, initiates an adjustment of the amplitude of the first audio channel and the amplitude of the second audio channel according to adjustment indicating signals stored in the mixer memory means.

According to a further aspect of the invention, both the audio mixer device and the video editor each include serial interface circuit means for converting control data from parallel form to serial form and transmitting said control data in serial form between said audio mixer device and said video editor.

According to yet another aspect of the invention, the audio follow video mixer system further comprises a serial communication cable operatively coupled to both said serial interface circuit means.

According to a further aspect of the invention, the audio mixer device is operable in an EDITOR mode, a MANUAL mode and an AUTO mode.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a representation of a typical mixer system according to the present invention.

FIG. 2 is a front view of a mixer console.

FIG. 3A and 3B are detailed views of a serial interface module portion of a mixer console.

FIG. 4 shows a circuit configuration for implementing the serial interface module of FIG. 3.

FIG. 5 is a block diagram illustrating a audio follow video mixer system according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 is a representation of a mixer system according to the present invention as used in a typical application. The system of FIG. 1 includes an editor 10 connected through a serial editor interface cable 20 to an audio follow video mixer 70. A plurality of multi-channel devices 80 are connected to the mixer 70 through several line input ports on the mixer. For convenience only, the following description will refer to VTRs, but it is to be understood that the invention is not so limited. Other devices, including other multi-channel devices, may be used with this invention.

As shown in FIG. 1, the editor 10 controls the operation of the audio follow video mixer 70 according to the signals from the video editor 10 supplied to a serial interface in the audio follow video mixer 70. The video editor 10 may also control the VTRs 80 through VTR control ports located on the VTRs. Peripheral devices, such as monitor devices 30 and effects modules 50A and 50B are provided to aid in mixing. In the example shown, the monitoring devices include two audio amplifiers 52 and 54 each associated respectively with a pair of audio speakers 56A and 56B, and 58A and 58B. With such a system, an operator of the video editor 10 may process several channels of input supplied to the mixer from different combinations of VTRs 80.

In such a system, the mixer is configured in such a way that each of the input audio channels from the VTRs are coupled to monitor and preview bus lines in the mixer. Once the system is configured, the operator may select two of the channels for editing. For example, a first channel A may be selected as an active channel to be faded out while a second inactive channel B may be selected to be faded in to full gain by use of a fader control member. The entire edit operation may be previewed in conjunction with monitoring devices 30, according to techniques known in the art.

FIG. 2 shows a front view of a mixer console 100 according to a preferred embodiment of the invention which may be employed in an audio follow video mixer configuration such as described above. In the mixer 100 shown, sixteen input modules 110A, 110B, 110C, 110D, 110E, 110F, 110G, 110H, 110I, 110J, 110K, 110L, 110M, 110N, 110O and 110P are present in the mixer console 100. These input modules provide inputs for several different audio channels which can then be processed in the mixer.

Also shown on the mixer console is a serial interface module 120. This module provides an interface between the mixer 100 and a video editor console, for example, as shown in FIG. 1. In combination with the input modules 110A through 110P, the serial interface module 120 allows a user to configure and operate the mixer from a video editor console operatively coupled to the serial interface. Alternatively, the mixer may be configured and operated at the mixer console, and configuration information provided to the video editor via the serial interface module 120.

FIGS. 3A and 3B show a serial interface module console 300. In this embodiment, several control switches and indicators are provided at a top portion 310 of the serial interface module console 300. These switches may be used to select various operating functions of the audio follow mixer system. These switches include a store button 312 and two preset buttons 314 and 316 for saving VTR configuration information.

Further shown in this figure is a mode select button 320 located on the control portion 310, and a plurality of mode indicator LEDs 320A, 320B, and 320C to visually indicate the operating mode of the audio follow mixer system. By pushing the mode select button 320, the operator may toggle through various operating modes. For example, the initial mode at power-up may be "EDITOR" mode. While in this mode, an EDITOR mode LED 320A will be illuminated. If the mode select button is then pushed, the mixer will change to an "AUTO" (local) mode, and the AUTO mode LED indicator 320B will be illuminated. If the mode select button is pushed again, the mode will be switched to a "MANUAL" mode, and the MANUAL mode LED indicator 320C will be illuminated. This cycle may be repeated by continuing to depress the mode select button 320. In this way, the mixer system can be operated under control of a video editor or operated locally.

The operation of the mixer is visually indicated by LED displays 322, 324, 326, and 328 which show respectively the number of the monitor machine, the duration of a crossfade, and the two machines "A" and "B" from which audio channels are provided for cross-fading. While not in editor mode, the monitor machine, the transition duration, as well as the A and B machines may be selected by various control buttons located on the serial interface module console.

In this example, each seven segment display element has two depressible buttons associated with it, one to increase the number displayed, the other to decrease it. Thus, the dual seven segment LED monitor machine display 322 has two pairs of select buttons 340A and 340B by which the left and right display elements can be changed, respectively. Similarly, the triple seven segment LED duration frame display 324 has three pairs of select buttons 342A, 342B and 342C for selecting the number of frames for an edit.

Likewise, an A machine and a B machine may be selected with the select buttons 346A, 346B, 348A, 348B which are associated with dual seven segment LED displays 326 and 328, as shown. Two single LEDs 350 and 352 are associated respectively with the A machine display 326 and the B machine display 328. If either of these LEDs 350 or 352 are illuminated, it indicates that the audio channel associated with that machine A or B is active, and therefore that machine is to be a "FROM" machine. Conversely, if LED 350 or 352 is not illuminated, it indicates that an audio channel of the associated A or B machine is to become active, that is the associated audio channel will be faded in to full gain, and therefore the machine is to be a "TO" machine.

In MANUAL mode, an operator can manually perform a crossfade between a selected TO machine and a selected FROM machine. In this example, fader slide controls 354 and 356 are used to perform edits between a selected A channel and a selected B channel. When a fader slide control is at the top position, the designated audio channel is set to full gain and the associated machine is the FROM machine. However, if the fader slide control is at the bottom position, the designated channel is set to zero gain and is the TO machine. Gain of the appropriate channel is controlled by a plurality of voltage controlled amplifiers (VCAs) located in the mixer, as is known in the art.

For example, if the A fader slide control 354 is at the top position and the B fader slide control 356 is at the bottom position, then the crossfade will be performed from channel A to channel B, that is, between the FROM machine indicated by the A machine display 326 and the TO machine indicated by the B machine display 328. This status will be indicated by illumination of the LED 350 and non-illumination of the LED 352.

According to this embodiment of the invention, a user can store a particular crossfade performed in MANUAL mode by use of a WRITE button 358 and a FADE LAW button 360 located on control portion 310 of the serial interface module 300. This operation is performed by repeatedly depressing the FADE LAW button 360, thereby toggling through various types of crossfade curves selectable in AUTO mode until CUSTOM crossfade is indicated by an LED indicator 368 (LED indicators 362, 364, and 366 indicate selection of the other types of crossfade curves). Once set to CUSTOM mode, the WRITE button 358 is enabled. Depressing the WRITE button then causes a subsequent crossfade performed by operation of the fader slide controllers 354 and 356 to be stored in memory. The storage of the crossfade will start once the fader slide controllers 354 and 356 are changed from the top or bottom. When the fader slide controllers 354 and 356 have reached their full transition, storage of the crossfade will cease.

MANUAL mode operation is further facilitated by use of a REVERSE select button 372. Depressing this button reverses the top and bottom positions of the B machine crossfader. That is, if the REVERSE select button 372 is depressed, if set to the top position, the fader slide controller 356 causes the B channel to be set to zero gain while in the bottom position, the fader slide controller 356 causes the B channel to set to full gain.

Once a custom crossfade has been stored, it can be used while the mixer is in AUTO mode or in EDITOR mode. For example, once placed in AUTO mode by appropriate operation of MODE select button 320, an operator can then select CUSTOM mode using the FADE LAW button 360 as above. The operator then selects the A machine and B machines which, when the mixer is in AUTO mode, indicate respectively the TO and FROM machines. The stored crossfade may then be performed by depressing a TRANSITION button 370 which then causes the stored crossfade to be initiated between the selected machines. In EDITOR mode, the transition may be initiated by an editor command from the video editor to the serial editor interface.

FIG. 4 illustrates a circuit configuration which may be used to implement the embodiment described in reference to FIG. 3. In this circuit, serial communication with a video editor is provided by use of a 9-pin connector 402 coupled to a serial communication interface circuit 404. This provides an interface between the audio follow video mixer and a video editor by which the above-described control signals can be uploaded and downloaded. For example, through this interface, the video editor can indicate that a custom crossfade stored in memory is to be performed.

The serial interface circuit of this embodiment further includes a central processing unit (CPU) 406 and a memory means 408. The memory provides control signals to the CPU 406 and further contains locations in which preset configurations and custom crossfades may be stored. The various indicators and displays, as discussed with reference to FIG. 3, are shown in FIG. 4. These indicators and displays are displayed under control of a display decoder and logic circuit 418 via lines 410, as shown.

Furthermore, a VCA switching logic circuit controls the operation of various VCAs associated with selected A and B channels via a VCA control circuit coupling the serial interface module with the VCA bus lines. The VCA switching logic circuit is operatively coupled to the fader slide controllers 354 and 356 and the REVERSE control button, as shown. Operation of the fader slide controllers 354 and 356 may control operation of various VCAs coupled to the VCA bus lines according to a technique well known in the art.

The display decoder and logic circuit 418 is provided to control the operation of the monitor machine display 322, the duration frame display 324, A machine display 326, and B machine display 328, as well as operation of the control buttons 330 340A, 340B, 342A, 342B, 342C, 346A, 346B, 348A and 348B that control the functions corresponding to these displays, as described above. The display decoder and logic circuit is further coupled to the MODE select button 320, FADE LAW button 360, WRITE button 358, and TRANSITION button 370 and the various LED indicators 358A, 368, 364, 362, 366, 320A, 320B, 320C, 350, 352 and 370A located on the serial interface module console as described above.

Controlled by the CPU 406, these elements are coupled along bus lines in the serial interface module to various control circuits which are further coupled to the buses located on the motherboard of the audio follow video mixer. Besides the above-described VCA control circuit 432, these control circuits include a preview command control circuit 434, an A/B crossfade control circuit 436, and a data address and buffer driver circuit 438. These control circuits provide means for controlling various operations of the audio channels provided to the mixer system according to control signals received from a video editor, or provided locally from the control portion 310 of the serial interface module console.

For example, operation of the MODE select button 320, FADE LAW button 360, WRITE button 358, and TRANSITION button 370 each causes an appropriate signal to be sent via display decoder and logic circuit 418 to the CPU 406. In turn the CPU 406 initiates the appropriate operation and display indication. More particularly, if set in CUSTOM and MANUAL modes, depression of the WRITE button 358 causes the particular digital control data which controls the appropriate VCAs located in the mixer to be saved in memory 408.

In this manner, it is possible for an operator to achieve a custom crossfade and to save it in the mixer for future use. This allows the operator to experiment with various different crossfades and conserve production time by having a desired custom curve stored.

Alternatively, according to the embodiment shown in FIG. 5, it is possible to save a custom crossfade by adding it to the EDL of the video editor. More specifically, once a crossfade has been "memorized" according to the technique described above, data corresponding to the custom crossfade is converted to serial data, for example in the serial communication interface circuit 404 of the serial interface module 400. This serial data is then uploaded from the mixer to the video editor 500 via a cable 505 where the data is converted to parallel data in an serial editor interface circuit 510. This data is then added, for example, by means of a microprocessor 520, to the EDL and stored in memory 530 provided in the video editor 500. This memory 530 may comprise either volatile or nonvolatile memory, but preferably the latter for the embodiment described below.

Once a custom crossfade has been uploaded to the video editor as described, it may then be stored for future use. Accordingly, once the mixer has been placed under control of the editor in the manner described above, a custom crossfade stored in the video editor memory may be downloaded to the mixer in serial format through the video editor serial interface and the serial communication interface circuit of the serial interface module. According to the preferred embodiment, the video editor and the mixer are operatively coupled in this manner via the 9-pin connector 402 shown in FIG. 4.

In this manner, greater versatility in editing of audio signals is provided. Specifically, the invention permits an operator to make greater use of a video editor which is used to control an audio follow video mixer.

From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. Accordingly, the invention is only limited by the claims set forth herein. 

What is claimed is:
 1. An audio follow video mixer system for performing a crossfade operation between a first audio channel having a first amplitude and a second audio channel having a second amplitude comprising,an audio mixer device which includes: gain control means for adjusting the amplitudes of the first audio channel and the second audio channel, said gain control means including means for manually controlling the adjustment of the amplitude of the first audio channel and the second audio channel and means for providing signals indicating the adjustment made to the first audio channel and the second audio channel; processor means for receiving said adjustment indicating signals; mixer memory means for storing data corresponding to said adjustment indicating signals; a first control member provided on a display portion of said audio follow video mixer, said first control member being operable to provide a store signal to said processor means to cause said processor means to provide said data corresponding to said adjustment indicating signals to said memory means; and a second control member provided on said display portion operable to cause said processor means to control said gain control means to adjust the amplitudes of the first audio channel and the second audio channel in accordance with said data stored in the memory means; and a video editor located remotely from said audio mixer device, said video editor being operatively coupled to said audio mixer device to receive said data stored in said mixer memory means; wherein said video editor includes editor memory means for storing said data and means for transmitting said data to said mixer apparatus.
 2. The audio follow video mixer system according to claim 1 further including a LED indicator for visually indicating that the first control member has enabled the storing of said data.
 3. The audio follow video mixer system according to claim 1 wherein both said audio mixer device and said video editor each include serial interface circuit means for converting said data stored in said mixer memory means and in said editor memory means from parallel form to serial form and transmitting said data in serial form between said audio mixer device and said video editor.
 4. The audio follow video mixer system according to claim 3 further comprising a serial communication cable operatively coupled to both said serial interface circuit means.
 5. The audio follow mixer system according to claim 4 wherein said audio mixer device is operable in an EDITOR mode in which said audio mixer is controlled remotely by said video editor, and a MANUAL mode in which said audio mixer is controlled manually by operation of a plurality of control members provided on said display portion.
 6. The apparatus according to claim 1 wherein said manual adjustment control means includes a third control member and a fourth control member each respectively coupled to gain control circuit means which control the amplitude of the first and second audio channels.
 7. An audio crossfade control apparatus comprising:an audio follow video mixer console; a gain control circuit provided in said mixer console for adjusting the respective amplitudes of a first output audio channel and a second output audio channel; a first manual adjustment member and a second manual adjustment member disposed on said mixer console and providing respective gain control signals to said gain control circuit to cause said gain control circuit to adjust said amplitudes of said first output audio channel and said second output audio channel; first memory means provided in said mixer console for storing data; first processor means operatively coupled to said gain control circuit, said memory means, said first manual adjustment member and said second manual adjustment member, said processor means providing data to said memory means which corresponds to said gain control signals; store control means provided on said mixer console operable to generate a store signal which is input to said processor means, said store signal causing said processor means to provide said data to said memory means; recall control means provided on said mixer console operable to generate a recall signal which is input to said processor means, said recall signal causing said processor means to read said data from said memory means and to provide gain control signals to said gain control circuit based on said data from said memory means; a video editor having second processor means and second memory means; and interface means for operatively coupling said first processor means within said mixer console with said second processor means with said video editor; wherein said video editor is operable to generate a second recall signal remotely causing said processor means to read said data from said memory means and to provide gain control signals to said gain control circuit based on said data from said memory means.
 8. The apparatus of claim 6 wherein said store control means comprises a plurality of control members which enable more than one set of data indicative of the amplitude adjustment of said first audio channel and said second audio channel to be stored in different locations in said first memory means.
 9. The apparatus of claim 6 wherein said store control means and said recall control means together comprise a write control member and at least one recall control member, wherein said write control member is operable to arm said first processor means to provide said data to said first memory means upon operation of said at least one recall control member, and said recall control member is otherwise operable independent of said write control member to cause said first processor means to provide said data to said first memory means.
 10. The apparatus of claim 8 wherein said at least one recall control member comprises two recall control members, each controlling the storage and recall of data in different locations in said first memory means.
 11. The apparatus of claim 8 further comprising a plurality of light emitting diodes, each associated with said write control member and said at least one recall control member to indicate the respective operations thereof. 